• Mycobiology
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• v.33 no.1
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• pp.1-6
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• 2005

Morphological characteristics of hyphal interaction between Grifola umbellata (Pers. Ex Fr.) Pilat and its companion fungus which related to sclerotia formation from hyphae were investigated by external observations, light microscopy and transmission electron microscopy (TEM). External observations showed that a dense antagonism line was formed by both G. umbellata and companion fungus after their hyphae contacted each other in dual culture. Many hyphal strands emerged on the colony of G. umbellata and differentiated to sclerotia from where hyphal strands crossed. Light microscope observations revealed the process of antagonism line formation. Mature antagonism with structural differentiation, was composed of three main layers: the rind, the rind underlayer and the hypha layer. TEM observations showed that after colonies hyphal contact, a series of reactions always occurred in both G. umbellata and companion fungus. Cells in the center of antagonism line were dead. Cells of G. umbellata adjacent to the antagonism line were usually large and hollow, with unilateral thickened wall, whereas those of companion fungus were empty, with thin or thick wall. Both hyphal interaction at the antagonism line may be one of the main reasons for sclerotia of G. umbellata differentiation from hypha.

• Microbiology and Biotechnology Letters
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• v.18 no.5
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• pp.449-453
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• 1990

This study was attempted to obtain the efficient milk-clotting enzyme from microorganisms as a rennet subtitute. Fungi which showed the formation ability of the milk-clotting enzyme were selected out from samples of soil hay and wastes etc. Among these isolated fungi, strain no. C-7 which had presented higher value in the ratio of milk-clotting activity to proteolytic activity was selected. The hyphae of this strain was white to gray and no septa. A single sporangiophore which stand erectly above growing hyphae was monomucor type without branching. A globose sporangium was developed at the tip of each sporangiophore. The suitable temperature and pH for the growth of no. C-7 was 20-$30^{\circ}C$ and pH 3.0-8.0 respectively. These morphological and physiological characteristics implied that strain no. C-7 was Mueor mucedo.

• Korean Journal of Organic Agriculture
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• v.13 no.2
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• pp.197-209
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• 2005

of Hangalku per plant sold for wild vegetables were 9.1g and 0.9g, and number of leaves was 10.8. Root fresh and dry weights of Hangalku per plant were 19.2g and 4.1g. Thirty five soil samples were collected from the native soils grown Cirsium japonicum DC., and mycorrhizal spores in soils were separated using wet-sieving methods. Number of mycorrhizal spores per 30g fresh soil sized over 500${\mu}$m, 355~500${\mu}$m, 251~354${\mu}$m, 107~250${\mu}$m and 45~106${\mu}$m were 0.6, 2.1, 6.0, 55.3 and 126, etc. Total number of mycorrhizal spores per 30g fresh soil were 190. Root infection by vesicles, hyphae and arbuscules were 13%, 4% and 3%, respectively. As a result of identification, mass propagated mycorrhizal spores by the host plant of Sudangrass were Glomus sp., Gigaspora sp., and Acaulospora sp., and so on.

• Korean Journal of Organic Agriculture
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• v.13 no.2
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• pp.175-184
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• 2005

This study was conducted to investigate into the distribution of arbuscular mycorrhizal fungi (AMF) in the greenhouse soils grown strawberry plants in Damyang and Jangheung districts. Twenty three soil samples were collected from strawberry plants under greenhouse conditions, and mycorrhizal spores in soils were separated using wet-sieving methods. Number of mycorrhizal spores per 30g fresh soil sized over 500${\mu}$m, 355~500${\mu}$m, 251~354${\mu}$m, 107~250${\mu}$m and $45{\sim}106{\mu}m$ were 0.3, 1.0, 4.2, 50.4 and 119, etc. Total number of spores per 30g fresh soil were l73.9. Root infection by vesicles and hyphae were 25% and 4%, respectively. Mycorrhizal root infection by arbuscules was not shown in strawberry roots. Isolated mycorrhizal spores were inoculated into the host plant of sudangrass to identify the genus of arbuscular mycorrhizal fungi, and propagated for 4 months. As a result of identification, mass propagated mycorrhizal spores were Glomus sp., Gigaspora sp., and Acaulospora sp., and so on.

• Korean Journal of Microbiology
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• v.28 no.1
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• pp.83-89
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• 1990

Two strains of actinomycetes producing extracellular adenosine deaminase, strain J-845S and strain J-326TK, were isolated from soil. Strain J-845S was gram-positive and non-acid-fast. This strain formed whitish, rod-shaped, smooth and non-motile spores on the aerial mycelium, and the spore chain was spiral. The hyphae of the mycelium branched abundantly. Cell wall chemotypes of the strain were of type I containing LL-diaminopimelic acids, and of phospholipid type II, and then strain J-845S was designated as Streptomyces sp.. Strain J-326TK was gram-positive and non-acid-fast. The hyphae of primary and aerial mycelium fragmented into irregular rod of coccus-like elements. The aerial mycelium either did not branch or sparsely branched. Cell wall composition was of type I and phospholipid type I. Thus, strain J-326TK was identified as Nocardioides sp.

• The Plant Pathology Journal
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• v.25 no.4
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• pp.376-380
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• 2009

Effects of silver nanoparticles on the phytopathogenic fungal growth were investigated. Fungal phytopathogens, especially for sclerotium-forming species Rhizoctonia solani, Sclerotinia sclerotiorum and S. minor, were selected due to their important roles in survival and disease cycle. Tests for the fungal hyphal growth revealed that silver nanoparticles remarkably inhibit the hyphal growth in a dose-dependent manner. Different antimicrobial efficiency of the silver nanoparticle was observed among the fungi on their hyphal growth in the following order, R. solani > S. sclerotiorum > S. minor. Tests for the sclerotial germination growth revealed that the nanoparticles showed significant inhibition effectiveness. In particular, the sclerotial germination growth of S. sclerotiorum was most effectively inhibited at low concentrations of silver nanoparticles. A microscopic observation revealed that hyphae exposed to silver nanoparticles were severely damaged, resulting in the separation of layers of hyphal wall and collapse of hyphae. This study suggests the possibility to use silver nanoparticles as an alternative to pesticides for scleotium-forming phytopathogenic fungal controls.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.2
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• pp.219-221
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• 2017

In 2015, white cottony tufts were observed on gametophytes of the kelp Saccharina japonica. Wet mount and histopathology examination revealed numerous fungal hyphae and mycelium around the gametophytes. The gametophytes surrounded by fungal hyphae were generally round and empty. A specific 610-bp fragment of the internal transcribed spacer (ITS)-5.8S rDNA-ITS gene of fungi was amplified by polymerase chain reaction and the nucleotide sequence showed 100% identity with those of Acremonium sclerotigenum, Acremonium sp. and Ascomycota sp. When fungus-infected gametophytes were mixed with healthy gametophytes, a high transmission rate (100%) resulted. This is the first report of mycosis of gametophytes in Korea.

• The Plant Pathology Journal
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• v.25 no.2
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• pp.113-120
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• 2009

Microscopic study of chili pepper (Capsicum annuum L.) infected with Phytophthora capsici, causing Phytophthora blight of chili pepper, was conducted to compare histological and cytological characteristics in the root and stem of susceptible (C. annuum cv. Bugang) and resistant (C. annuum cv. CM334) pepper cultivars. The susceptible pepper roots and stems were extensively penetrated and invaded by the pathogen initially into epidermal cells and later cortical and vascular cells. Host cell walls adjacent to and invaded by the infecting hyphae were partially dissolved and structurally loosened with fine fibrillar materials probably by cell wall-degrading enzymes of the pathogen. In the resistant pepper, the pathogen remained on root epidermal surface at one day after inoculation, embedded and captured in root exudation materials composed of proteins and polysaccharides. Also the pathogen appeared to be blocked in its progression at the early infection stages by thickened middle lamellae. At 3 days after inoculation, the oomycete hyphae were still confined to epidermal cells of the root and at most outer peripheral cortical cells of the stem, resulting from their invasion blocked by wound periderms formed underneath the infection sites and/or cell wall appositions bounding the hyphal protrusions. All of these aspects suggest that limitation of disease development in the resistant pepper may be due to the inhibition of the pathogen penetration, infection, invasion, and colonization by the defense structures such as root exudation materials, thickened middle lamellae, wound peridems and cell wall appositions.

• Tuberculosis and Respiratory Diseases
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• v.49 no.4
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• pp.508-513
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• 2000

The aspergillus tracheobronchitis is distinctive manifestation of invasive aspergillosis, in which infection is limited completely or predominantly to the tracheobronchial tree. It accounts for about 7 to 10 percent of cases of invasive disease. Grossly, such disease may take the mucosal exudate and obstruct partially the airway lumen or completely the occlusive mucous/fungus plugs. Microscopically, the superficial portion of the airway wall is acutely inflamed and contain fungal hyphae. However, infection is often limited to the mucosa. We report a case of aspergillus tracheobrochitis in a 54 year-old man who presented cough, progressive dyspnea with wheezing, and mucus plug. Bronchoscopy showed mucosal exudate and plug. Bronchoscopic biopsy showed aspergillus hyphae and inflammation in the mucosa. He was successfully treated with itraconazole.

• The Plant Pathology Journal
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• v.34 no.2
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• pp.113-120
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• 2018

Chlorella, one single-cell green algae organism that lives autotrophically by photosynthesis, can directly suppress some plant diseases. The objective of this study was to determine whether pre-spraying with Chlorella fusca suspension could induce systemic acquired resistance (SAR) in cucumber plants against anthracnose caused by Colletotrichum orbiculare. In order to illustrate SAR induced by algae, infection structures in host cells were observed under a transmission electron microscope (TEM). Cytological changes as defense responses of host mesophyll cells such as accumulation of vesicles, formation of sheath around penetration hyphae, and thickness of cell wells adjoining with intracellular hyphae were demonstrated in cucumber leaves. Similar defense responses were also found in the plant pre-treated with DL-3-aminobutyric acid, another SAR priming agent. Images showed that defense response of host cells was scarcely observed in untreated leaf tissues. These cytological observations suggest that C. fusca could induce SAR against anthracnose in cucumber plants by activating defense responses of host cells.